Mnuchin's next-door neighbor on Bel Air Road received a suspicious package addressed to Mnuchin, according to LAPD West Los Angeles Area Watch Commander Rob Weise. The package -- which contained horse manure -- was dropped off at a neighbor's house. It was cleared by investigators around 8 p.m.

The Secret Service was also involved due to the connection to Mnuchin.

Mnuchin was at his home at the time of the incident and "was made aware of the situation," but was not in immediate danger, Weise said.